85 300td shut off issue

[connerm]

Engine stops, although very slowly, when I remove the key and the doors are locked. Otherwise I have to hit the stop lever. This issue came on all of a sudden. I can't even get it to shut off even when I put the mityvac on the vacuum control valve. All connections are still good and rubber connectors are only a couple of years old.

Does this sound like a leak in the door locks somewhere or is the vcv shot?